Kong Weiyu, Bao Yang, Lu Liguo, Han Zhipeng, Zhong Yifan, Zhang Ran, Li Yuqiang, Yin Guoyin
The Institute for Advanced Studies, Wuhan University, Wuhan, Hubei, 430072, P. R. China.
Core Facility of Wuhan University, Wuhan, Hubei, 430072, P. R. China.
Angew Chem Int Ed Engl. 2023 Aug 28;62(35):e202308041. doi: 10.1002/anie.202308041. Epub 2023 Jul 19.
While chain-walking stimulates wide interest in both polymerization and organic synthesis, site- and stereoselective control of chain-walking on rings is still a challenging task in the realm of organometallic catalysis. Inspired by a controllable chain-walking on cyclohexane rings in olefin polymerization, we have developed a set of chain-walking carboborations of cyclohexenes based on nickel catalysis. Different from the 1,4-trans-selectivity disclosed in polymer science, a high level of 1,3-regio- and cis-stereoselectivity is obtained in our reactions. Mechanistically, we discovery that the base affects the reduction ability of B pin and different bases lead to different catalytic cycles and different regioselective products (1,2- Vs 1,3-addition). This study provides a concise and modular method for the synthesis of 1,3-disubstituted cyclohexylboron compounds. The incorporation of a readily modifiable boronate group greatly enhances the value of this method, the synthetic potential of which was highlighted by the synthesis of a series of high-valued commercial chemicals and pharmaceutically interesting molecules.
虽然链行走引发了人们对聚合反应和有机合成的广泛兴趣，但在有机金属催化领域，对环上链行走的位点和立体选择性控制仍然是一项具有挑战性的任务。受烯烃聚合中可控的环己烷环上链行走的启发，我们开发了一组基于镍催化的环己烯链行走碳硼化反应。与聚合物科学中公开的1,4-反式选择性不同，我们的反应获得了高水平的1,3-区域和顺式立体选择性。从机理上讲，我们发现碱会影响Bpin的还原能力，不同的碱会导致不同的催化循环和不同的区域选择性产物（1,2-加成与1,3-加成）。这项研究为合成1,3-二取代环己基硼化合物提供了一种简洁且模块化的方法。易于修饰的硼酸酯基团的引入大大提高了该方法的价值，一系列高价值商业化学品和具有药学意义的分子的合成突出了其合成潜力。
